Art of vulcanizing rubber



w s Aug; 2,1927;

UNlT-ED STATES PATENT OFFICE.

am rarrm or AKRON, omo, assrenon r run Goonvm'n arms & RUBBER cou- PANY,OF AKRON, OHIO, A CORPORATION OF OHIO.

am: or vuncamzmc 31133123.

in, Drawing. Original application filed February 12, 1926, Serial No.87,949. Divided and um applicatlon filed November 3, 1926. Serial No.146,068.

My invention relates to the art of manufacturing vulcanized rubbercompositlons and it has particular reference to the em-' ployment of aclass of chemical compounds that accelerate the process ofvulcanization. The object of the invention is to provide a new class ofchemical compounds that are capable of accelerating the vulcanizationreactions andv imparting desirable physlcal properties to thevulcanizate. eneric class of chemical compounds embo ying a thiazolegroup as a part of their structure is disclosed in the patent to Sebrelland Bedford, No. 1,544,687, July 5, 1925.

.These compounds, particularly those having a mercapto group joined tothe thiazole ring, at position 2, indicated under. approvednomenclature, have been found to be excellent accelerators. A 'spbacificcompound of this so classiis 2-mercapto enzoth1azole:

430- name of Lorin BQSebrell, Serial Number 87 ,95 O,dated February 12,1926, there is disclosed a large number of substances, that have beendiscovered to be suitable for use as accelerators. This class ofcompounds in- ]'cludes addition or substitution products of chemicalshaving as .a part of their structure a thiazole group, as for example,6-mtro-2- mercaptobenzothia'zole: v

'The present-disclosure relates to certain in isomer of this'material,the 6-chlor 90 2-mercaptobenzothiaziole, which may be presolution underordinary or slightly increased species of the substitution or additionproducts of mercaptothiazoles, and it has articular reference tothe-halogen derivatives and the salts thereof that have been found to beuseful in the manufacture of rubber products. It is deemed unnecessaryfor a proper understanding of this invention to describe the variousmethods of forming these compounds, inasmuch as certain methods areknown and others are disclosed in the copending application of Sebrelland Teppema, Serial Number 37,861, filed J une 7, 1925.

Accelerators that impart desirable 'ualities to the rubber compositionsare pr uced by joining to the adjacent carbon atoms of the-thiazole'ring, one or more radicals that include a halogen atom. The radicals soadded may be either aliphatic 'or cyclic, and

may be aryl radicals having a portion of their structure common to thethiazole ring. An example of the latter group is2-mercaptobenzothiazole, a species of the class ofmercaptoarylthiaz'oles, which may be united with a halogen atom to forma compound of the class specified herein. A compound that may beregarded as typical of halogen mercaptobenzothiazoles is5-ch1or-2-mercaptobenzothiazole, represented structurally as: l

- i--.s1i

Y Y 3 so This compound may be prepared from-14- dichlor-nitro-benzene.1-4-dichlor- 2-nitr0- benzene is treated with sodium hydrosulphide andcarbon bisulphide in an aqueous pressure. The reactions may be indicatedas follows:

pared conveniently by diaaotizing fiamido 2-mercaptobenzothiazole islikewise an acoel- 'ization of vcaoutchonc that comprises vu1can zationof caoutchouc that comprlses vulcanerator ha 1 desirable properties. Itmay.

-be designs. structurally in this manner;

'Many derivatives including the metallic salts, disulfide or thecorresponding tolyl, naphthyl and anisyl thiazole are merelymodifications of the broad idea, which has been set forth above.

The following are representative results which have been ob-' tainedwhen this class of materials were compounded in a mix having thefollowing ratio r of ingredients: 100 parts rubber, 5 parts zno, 3 partssulfur, 0.5 part accelerator.

' The principles of the invention have been disclosed with particularreference to a few specific compounds which fall within the scopethereof, but it is to be understood that these are presented asexemplifying theinvention rather than limiting it. It isi-ntended,'therefore,'that only those limitations should be imposedwhich are requ' red by the scope of the following claims.

What-I claim isr 1. A method of {acceleratingthe vulcanization ofcaoutchoucthatcomprises vulcan izing the same in the presence of ametallic salt of a halogen derivativeof a mercapto benzothiazole. V

'2. A method of accelerating the vulcanizing the same in the presence ofa zincsalt of a halogen derivative of a mercaptobenzothiazole. o r i 3.A method of acceleratlng the Yllllllh zation of caoutch'ouc thatcomprises vulcanizing the same in the presence .of a metallic salt of achlorine derivative of a mercaptobenzothiazole.

4. A method of accelerating the vulcan1- nee-1,191

izing the same in the presenceof a zmcsalt of a' chlorine derivative ofa mercaptobenzothiazole.- 1

5. A method of nation of caoutchouc that comprises vulcanizing the samein thepresence of a metallic accelerating the vulcanisalt ofa halogenderivative of a mercapto benzothlazole having a nitrogen containinggroup substituted in its aryl structure.

6. A method of accelerating the vulcani-- zation of caoutchouc thatcomprises vulcanlzlng the same 1n the presence of a metallic salt'of ahalogen derivative of the mercapto-- benzothiazole having an amido groupsub stituted in its aryl structure. a

' A'method of acceleratlng the vulcani zatlon of caoutchouc thatcomprises vulcan- 1 izing the same in the presence of a zinc salt of ahalogen derivative of a mercaptobenjzothiazole having a nitrogencontaining group substituted in. its aryl'structure.

.- 8. A method of accelerating thevulcani zation ofcaoutchouc thatcomprises Vulcan izing. the same in the; presence of a zinc salt of ahalogen derivative ar mercapto- 'benzothiazole having an amide 'groupsubstitute'd in its aryl' structure.

95A method of accelerating the vulcanization of caoutchouc thatcomprises vulcanzlng the same 1n the presence of a zinc salt of achlorine der vative of a mercaptobenzothiazole having a nitrogencontaining group substituted in its aryl structure.

10. A method of accelerating the vulcanization of caoutchouctthatcomprises vulcanizing the same in thdpresenceof a zinc salt 7 of 5-chlor6-amido 2-mercaptobenzothiazole.

I 11. A caoutchouc that has been vulcanized in the presence of ametallic salt of a halogen derivative of a mercaptobenzothiazole. 12. Acaoutchouc that has been vulcanized in the presence of a' zinc salt of ahalogen derivative of a m'e'rcaptobenzothiazole.

13. A caoutchouc that has been vulcanized in the presence of a metallicsalt of a chlorine derivative of a mercaptobenzothiazole.

14-. A caoutchouc that has been vulcanized in the presence of a zincsalt of a chlorine derivative of a mercaptobenzothiazole.

15.- A caoutcliouc that has been vulcanized signed my name.

7 JAN TEPPEMA.

